The present invention relates to a condenser suitable for use in, for example, a car air conditioner, which is a refrigeration cycle mounted on an automobile.
Herein and in the appended claims, the term “condenser” encompasses not only ordinary condensers but also sub-cool condensers each including a condensation section and a super-cooling section.
Further, herein and in the appended claims, the upper side, lower side, left-hand side, and right-hand side of FIGS. 1 and 2 will be referred to as “upper,” “lower,” “left,” and “right,” respectively.
A condenser for a car air conditioner is known (see Japanese Utility Model Application Laid-Open (kokai) No. H3-31266). The known condenser includes a plurality of flat heat exchange tubes which extend in a left-right direction and are disposed in parallel such that their width direction coincides with an air passage direction, and they are spaced apart from one another in a vertical direction; and header tanks which extend in the vertical direction and to which left and right end portions of the heat exchange tubes are connected, respectively. Three heat exchange paths each formed by a plurality of heat exchange tubes successively arranged in the vertical direction are provided such that the three heat exchange paths are juxtaposed in the vertical direction. Refrigerant flows in the same direction through all the heat exchange tubes which form each heat exchange path, and the flow direction of refrigerant flowing through the heat exchange tubes which form one of two adjacent heat exchange paths is opposite the flow direction of refrigerant flowing through the heat exchange tubes which form the other heat exchange path. A first header tank and a second header tank are individually provided at the left end or right end. The heat exchange tubes which form the heat exchange path at the lower end are connected to the first header tank. The heat exchange tubes which form the heat exchange paths other than the lower-end heat exchange path are connected to the second header tank. The second header tank is disposed above the first header tank. The thickness (diameter) of the first header tank is rendered considerably larger than that of the second header tank, and a desiccant is disposed within the first header tank. Thus, the first header tank functions as a liquid receiver which separates gas and liquid from each other by making use of gravitational force and stores the separated liquid. The first heat exchange tubes connected to the first header tank are equal in length to the second heat exchange tubes connected to the second header tank, and the ends of the first heat exchange tubes on the side toward the first header tank and the ends of the second heat exchange tubes on the side toward the second header tank are located on the same vertical line. All the heat exchange paths serve as refrigerant condensation paths for condensing refrigerant.
In the condenser disclosed in the publication, the internal volume of the first header tank must be rendered considerably large as compared with that of the second header tank, in order to effectively perform gas liquid separation within the first header tank. Therefore, the thickness of the first header tank is considerably large as compared with the second header tank, which raises a problem in that a large space is required for installing the condenser.
In general, other devices are disposed in the vicinity of a condenser. In the case of the condenser disclosed in the publication, the first header tank hinders installation of other devices. For example, a radiator is typically disposed downstream (with respect to an air passage direction) of a condenser for a car air conditioner. If the condenser disclosed in the publication is used, the first header tank hinders installation of the radiator. As a result, a wasteful space is produced within an engine compartment, which makes space saving difficult. In addition, since the heat exchange tubes are connected over substantially the entire length of the first header tank, the conventional condenser has a problem in that its gas liquid separation performance is not satisfactory.